This invention concerns an apparatus for a tool used when performing a machining operation, and more specifically to a boring tool used with a Computer Numerically Controlled (CNC) boring machine.
Many products, such as automotive transmission housing and engine blocks, include precision bored holes. These holes are bored by cutting tools supported by a boring tool which is driven by a boring machine. In many situations, the boring machine is computer numerically controlled (CNC) for reasons of flexibility, economics, and precision. Many CNC boring machines are capable of performing a wide range of operations on a product, including the boring of many different sizes of holes, by the automatic selection of a previously adjusted boring tool from a tool bank.
However, many boring tools require manual adjustment by the machine operator. Some currently used boring tools, such as the 3F-HBD Boring and Facing Head by Criterion Machine Works of Costa Mesa, Calif.; and the tools of the Starflex Boring Tool Program of the Johne+ Company of Germany require manual adjustment of the position of the cutting tool corresponding to the desired bore diameter. Some tools include an internal worm gear adjustable by the operator with an Allen wrench to slide a tool holder within a groove of a machine coupling member. After the operator has manually positioned the cutting tool to bore the correct size diameter, the operator then tightens one or more fasteners to lock the position of the tool holder relative to the machine coupling element. Thus, the clamping force holding the cutting tool on the boring tool is not maintained during adjustment and the tool is reclamped after adjustment. This slow, inflexible, labor-intensive adjustment method detracts from the speed and economy of the CNC machine by requiring the operator to stop the operation of the CNC machine during the period of adjustment.
What is needed is a boring tool which permits adjustment of the position of the cutting tool by operation of the machine, and not by manual readjustment. Further, what is needed is a method of adjusting a boring tool on a CNC machine by software commands. The present invention overcomes the drawbacks of the related art in novel and unobvious ways.
One embodiment of the present invention is a unique method to adjust the position of a cutting tool. Other embodiments include unique apparatus, methods, systems, and devices for adjusting the position of a cutting tool.
A further embodiment of the present invention pertains to adjusting the position of a cutting tool used in a boring operation. The cutting tool is slidably coupled to the boring tool with a frictional force sufficient to hold the cutting tool steady during machining of a bore, but insufficient frictional force to prevent the adjustment of the lateral position of the cutting tool.
Still another embodiment of the present invention pertains to a machining apparatus in which a cutting tool is slidably coupled to a tool apparatus. The tool apparatus includes a mechanism for applying varying amounts of frictional force against the sliding tool holder.
Yet another embodiment of the present invention relates to a method for adjusting the sliding position of a cutting tool. The method includes sliding the cutting tool in a first direction to a first predetermined position. The cutting tool is then moved in a second direction opposite to the first direction to a second predetermined position.
In yet another embodiment of the present invention, there is a method for machining an object. The method includes coupling a boring tool to a boring machine, and clamping a slidable cutting tool to the boring tool. The lateral position of the cutting tool is changed while maintaining the coupling and clamping. After the position of the cutting tool has been changed, the object is machined while maintaining the coupling and clamping.
Yet another embodiment of the present invention includes a system for boring a hole. The system includes a computer numerically controlled machining apparatus having an electronic controller. The electronic controller adjusts the sliding position of the cutting tool holder by placing a surface of the cutting tool holder in contact with a second surface of a static member. The electronic controller commands the machining apparatus to apply a force across the surfaces in contact.
A still further embodiment of the present invention includes an apparatus for boring a hole. The apparatus includes means for applying a normal force between first and second contact surfaces. The normal force creates a predetermined frictional force sufficient to restrain the position of the tool holder when the cutting tool is boring a hole, but which predetermined frictional force is insufficient to restrain the lateral position of tool holder when the lateral position of the tool holder is adjusted.
A still further embodiment of the present invention includes an apparatus for machining a hole with a boring machine. The apparatus includes a movable tool holder slidably coupled to a coupling element. A spring urges a contact surface of the tool holder against a contact surface of the coupling element.
Yet another embodiment of the present invention includes an actuating mechanism which varies the contact force between a cutting tool holder and a coupling member. The mechanism is actuatable between a first state in which a first contact force is applied in a direction at least partly parallel to the rotational axis of the cutting tool holder, and a second state in which the mechanism is actuatable to provide a second contact force greater than the first contact force in a direction at least partly parallel to the rotational axis.
A still further embodiment of the present invention includes a method for boring a hole in an object, wherein a surface of the cutting tool holder slides against a surface of a static member placed proximate to the boring tool. The surface of the cutting tool holder slides against the surface of the static member during machining of the object.
In yet another embodiment of the present invention, there is a contoured surface on either an external surface of a slidable cutting tool holder, or on an external surface of a static member. The contour corresponds to the contour of the sidewalls of the hole to be bored. The surfaces of the cutting tool holder and static member are in contact during machining of the hole. Accordingly, one object of the present invention is to provide a unique method for adjusting the position of a cutting tool.
Another object of the present invention is to provide a unique method for machining a contoured sidewall of a hole.
Further objects, embodiments, forms, benefits, aspects, features, and advantages of the present invention can be obtained from the description, drawings, and claims provided herein.